Position searching method and apparatus based on electronic map

ABSTRACT

The present invention relates to electronic maps, and provides a position searching method and apparatus based on an electronic map. The method includes: receiving a keyword of a searching object; searching the electronic map with the keyword to obtain a current geographical position; acquiring panoramic images of a plurality of scenes that are located within a geographical area around the current geographical position and of a predetermined size; calculating coordinates of the searching object in one of the panoramic images according to position-related information of each scene; generating an image from an image area of the one of the panoramic images and outputting the image, wherein the image area is centered on the coordinates and of a predetermined size. The present invention can accurately position an image associated with the searching object, and has the advantages of low cost and less amount of data.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 14/364,565, entitled “POSITION SEARCHING METHOD ANDAPPARATUS BASED ON ELECTRONIC MAP”, filed Jun. 11, 2014, which is a 371National Phase application of PCT/CN2013/076201, entitled “POSITIONSEARCHING METHOD AND APPARATUS BASED ON ELECTRONIC MAP”, filed May 24,2013, which claims priority to Chinese Patent Application No.201210167958.0, entitled “POSITION SEARCHING METHOD AND APPARATUS BASEDON ELECTRONIC MAP”, filed on May 28, 2012, all of which are incorporatedherein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to electronic maps, and more particularlyto a position searching method and apparatus based on an electronic map.

BACKGROUND OF THE INVENTION

Statistical data shows that position searching, for example, searchingthe geographical position of shopping malls, hotels, and schools, orfinding all the nearest restaurants and cinemas around the user, is themajor need when users using electronic maps. As the technology develops,the results of position searching are becoming richer and richer. Exceptthe accurate place can be positioned, additional text information suchas addresses, telephone numbers, and comments, and image information canalso be provided. Due to the visual and intuitive features, images arebecoming an important manner for showing position-related information.However, in the known art, the images are mainly uploaded by users orsearched from the web, and thus, these images suffer from the followingdrawbacks.

1) These images have poor correlation to the searching object. Forexample, some images can't correctly show the position of the searchingobject, and evenly have none business of the searching object.

2) It is costly and of low efficiency to associate these images tocorrect positions. The images uploaded by users or searched from the webare full of randomness, and the data content is irregular. Thus, manualreviewing is necessary to associate these images to correct positions.Generally, the ratio of the approved images is very low.

SUMMARY OF THE INVENTION

Various embodiments of the present disclosure provide a positionsearching method and apparatus based on an electronic map, therebysolving the problems of high cost and low correlation in the process ofassociating images to geographical positions using the known positionsearching techniques.

In one embodiment, a position searching method is provided, and themethod includes the following steps:

receiving a keyword of a searching object;

searching the electronic map with the keyword to obtain a currentgeographical position of the searching object;

acquiring panoramic images of a plurality of scenes that are locatedwithin a geographical area around the current geographical position andof a predetermined size;

calculating coordinates of the searching object in one of the panoramicimages according to position-related information of each scene;

generating an image from an image area of the one of the panoramicimages and outputting the image, wherein the image area is centered onthe coordinates and of a predetermined size.

In one embodiment, a position searching apparatus is provided. Theapparatus includes:

a keyword receiving unit, configured for receiving a keyword of asearching object;

a position obtaining unit, configured for searching the electronic mapwith the keyword to obtain a current geographical position of thesearching object;

a panoramic image acquiring unit, configured for acquiring panoramicimages of a plurality of scenes that are located within a geographicalarea around the current geographical position and of a predeterminedsize;

a coordinates calculating unit, configured for calculating coordinatesof the searching object in one of the panoramic images according toposition-related information of each scene;

an image outputting unit, generating an image from an image area of theone of the panoramic images and outputting the image, wherein the imagearea is centered on the coordinates and of a predetermined size.

The embodiments of the present invention obtain the current geographicalposition of the searching object from the electronic map according tothe keyword. Then, panoramic images of a plurality of scenes that arelocated within a geographical area are obtained. After that, coordinatesof the searching object in one of the panoramic images can be calculatedaccording to position-related information of each of the scenes.Finally, an image is generated from an image area of the one of thepanoramic images and outputted, wherein the image area is centered onthe coordinates and of a predetermined size. The embodiments overcomethe problems of the know position searching method for obtaining animage such as high cost and low correlation to the searching object. Theabove embodiments can accurately show image information for ageographical position. In addition, the above embodiments can beachieved at a low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a flow chart of a position searching method based onan electronic map in accordance with a first embodiment.

FIG. 2 is a schematic view showing all the scenes in a geographical areain accordance with an embodiment.

FIG. 3 is a schematic view showing a panoramic image of a scene that iscentered on a head of a car in accordance with an embodiment.

FIG. 4 is a schematic view showing a geographical position of asearching object and a scene in accordance with an embodiment.

FIG. 5 is a schematic view showing a result of the position searchingmethod based on an electronic map in accordance with an embodiment.

FIG. 6 is a block diagram of a position searching apparatus inaccordance with a second embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

To make the technical solutions and advantages of the present inventionmore apparently, embodiments of the present invention will be describedin detail accompanying with figures as follows. It is to be noted that,the embodiments described here are used to illustrate the presentinvention, but are not intended to limit the present invention.

In the embodiments of the present invention, a current geographicalposition of a searching object is obtained from an electronic mapaccording to a keyword of the searching object. Then, panoramic imagesof a plurality of scenes that are located within a geographical areaaround the current geographical position and of a predetermined size areacquired. After that, coordinates of the searching object in one of thepanoramic images are calculated according to position-relatedinformation of all the scenes. Finally, an image is generated from animage area of the one of the panoramic images and outputted, wherein theimage area is centered on the coordinates and of a predetermined size.As a result, the embodiments of the present invention are capable ofaccurately obtaining images of high correlation to the searching objectfrom preserved panoramic images based on a low cost manner, and theimage utilization ratio is improved.

The exemplary implementation of the present invention is described indetail below in conjunction with the specific embodiments.

Embodiment 1

FIG. 1 illustrates a flow chart of a position searching method based onan electronic map in accordance with a first embodiment. The method isdescribed in details as follows.

Panoramic images (i.e., 360-degree panoramic images) are images capturedby panoramic cameras. As panoramic images are usually two-dimensionalimages transformed by a special projection, a special player may be usedto project a panoramic image to generate a three-dimensional renderingfor the user. By taking a lot of panoramic images at different positions(scenes) along a road or a street and combine these panoramic imagestogether, a street view can be provided. Compared with general photos,the street view has the following advantages: 1) strong sense ofimmersion, and providing a fully immersive feeling for the user; 2) allthe images have associated geographical information, which is convenientto position the images; 3) the images are taken along streets in batch,and thus covering a lot of positions; 4) it is convenient to generate animage, the production cycle is short, and the production cost is low.Because a street view has the above advantages, it is very suitable forproducing position-related images. A street view is composed of aplurality of scenes arranged along a street, and each scene has locationinformation describing a geographical position of the scene and apanoramic image centered on the geographical position. FIG. 2 shows allthe scenes in a certain area of the street view. As shown in FIG. 2, thescenes are sequentially arranged along a road, and each dot representsthe position of a corresponding scene. The distance between each twoadjacent dots is even.

FIG. 3 shows a stitched 360-degree panoramic image of a scene that iscentered on a head of a car. The panoramic image has a width of w and aheight of h, with w and h being equal to the number of pixels of thepanoramic image in the horizontal and vertical directions, respectively.The direction of the head of the car, or in other words, heading angleis θ₀. From the left to the right, the heading angle ranges from 0degrees to 360 degrees. Therefore, for any target, if the heading angleθ of the target in the panoramic image is given, a position (X, Y) ofthe target in the panoramic image can be calculated by the followingformula (1):

X=h/2;

Y=w/2+(θ−θ₀)*w/360;  (1)

It is to be noted that the heading angle θ or θ₀, the geographicalposition of the scenes should be described in a same coordinate system.In the present embodiment, the coordinate system is the map coordinatesystem. That is, a certain scene point is the center or in other wordsthe original point, the north direction is the positive direction of theX axis, the south direction is the negative direction of the X axis, thewest direction is the negative direction of the Y axis, and the eastdirection is the positive direction of the Y axis. Additionally, in theabove formula (1), if the calculated result Y exceeds a range [0, w],“w” can be added or subtracted from Y until Y is in the range [0, w].

In step S101, a keyword of a searching object is received.

In step S102, a current geographical position of the searching object isobtained by searching an electronic map with the keyword.

In a step S103, panoramic images of a plurality of scenes that arelocated within a geographical area around the current geographicalposition and of a predetermined size are acquired.

In a specific implementation process, when a user wants to obtain thegeographical position of a searching object, a keyword related to thesearching object can be inputted into the electronic map. For example,if the user wants to obtain the geographical position of “JinrunBuilding” in a city, a keyword “Jinrun Building” can be inputted intothe electronic map. At this point, the current geographical position ofthe searching object represented by the keyword “Jinrun Building”, inother words, the geographical position outputted by the electronic map,is obtained. Thus, the specific location can be displayed in theelectronic map, and simultaneously, additional information such astelephone numbers, names, addresses and traffic lines related to thesearching object can also be displayed.

Furthermore, it is necessary to prepare panoramic images correspondingto the electronic map. The panoramic images are two-dimensional imagescorresponding to a plurality of scenes of a street view, and there isposition-related information for all the scenes. The position-relatedinformation for each scene includes the width and height of acorresponding panoramic image, the geographical position and the headingangle of the scene. After obtaining the geographical position of thesearching object, a plurality of scenes that are near to the currentgeographical position of the searching object may be obtained. The imageinformation of the searching object can be viewed from all these scenes.However, the searching object can't be viewed from the scenes that arefar away from the current geographical position. As the street viewincludes a great number of scenes, thus it is necessary to limit thescenes in a geographical area. The panoramic images of all the scenes inthe geographical area include the searching object, in other words, thecurrent geographical position of the searching object can be viewed fromthe panoramic images of the scenes in the geographical area. Forexample, the scenes can be limited in a circular area centered on thecurrent geographical position. However, the area is not limited to this,and the user may set the area according to the practical requirements.Generally, the scenes that have a distance of less than 100 meters fromthe current geographical position can be selected. Then, the operationcan only be performed on the scenes in the geographical area, and thusthe amount of data is decreased and it is very suitable for some trafficsensitive applications such as mobile phones.

In a step S104, coordinates of the searching object in one of thepanoramic images are calculated according to position-relatedinformation of each scene.

The step S104 may include the following steps:

obtaining a geographical position (x2, y2) of a nearest scene of thecurrent geographical position (x1, y1) of the searching object accordingto the geographical position of each of the scenes in the geographicalarea;

calculating a heading angle θ=a tan 2((x2−x1), (y2−y1)) of the searchingobject in a panoramic image of the nearest scene according to thecurrent geographic position and the geographic position of the nearestscene; and

calculating the coordinates (x0, y0) of the searching object in thepanoramic image of the nearest scene according to the heading angle θand position-related information of the nearest scene.

(x₀, y₀) can be calculated referring to the above formula (1).

x0=h/2;

y0=w/2+(θ−θ₀)*w/360;

wherein h, w and θ₀ represent the height, the width, and the headingangle of a panoramic image corresponding to the nearest scene,respectively, and θ represents a heading angle of the searching object.

In a specific implementation process, after obtaining the panoramicimages of the scenes in the geographical area in step 103, theposition-related information of all the scenes in the geographical areacan further be obtained. Then, the distance between the geographicalposition of each scene and the current geographical position (x₁, y₁) ofthe searching object can be calculated. Accordingly, the scene that hasa minimum distance is selected as the above nearest scene, and thegeographical position of this nearest scene is (x₂, y₂). A distancebetween (x₂, y₂) and (x₁, y₁) can be calculated by the followingformula: D=√{square root over ((x2−x1)²+(y2−y1)²)}. The heading angle ofthe searching object in the panoramic image of the nearest scene can becalculated by the following formula: θ=a tan 2((x₂−x₁), (y₂−y₁)). Asshown in FIG. 4, a dot A represents the geographical position of thesearching object “Jinrun Building”, a dot B represents the geographicalposition of a scene that is nearest to the dot A, a distance between Aand B is D, and a heading angle of the searching object in the panoramicimage is θ. Combining with the width w, the height h, and the headingangle of the panoramic image of the scene at the dot B, the coordinates(x₀, y₀) of the searching object “Jinrun Building” can be calculated.

In the present embodiment, after performing the step 104, the method mayfurther includes the following step:

projecting the panoramic image to generate a three-dimensional image,and,

updating the panoramic image to the three-dimensional image.

In detail, because the panoramic images are two-dimensional images thatare taken from the scene in the real world using cameras, the imagefinally displayed to the user is also a two-dimensional image if it isdirectly cut from the panoramic image but not projected to be athree-dimensional image first, and this could affect the visual effectof the displayed image. To enhance the user's experience, the panoramicimage can be projected to output an image. As shown in FIG. 3, takingthe panoramic image including “curved road” as an example, the road inthe two-dimensional image is curved due to the panoramic projection.Actually, the “curved road” is straight. By projecting the panoramicimage using a panoramic algorithm, an image without transformation anddistortion can be obtained, and the obtained image can be displayed tothe user for better visual effect.

In a step S105, an image is generated from an image area of the one ofthe panoramic images and outputted, wherein the image is centered on thecoordinates and of a predetermined size.

In a specific implementation process, the finally outputted image can bea part of the panoramic image that is in a circular area centered on thecoordinates and having a designated radius, or in a rectangular areacentered on the coordinates and having a designated width and height. Ifthe image area is rectangular, a width W and a height H of the imagearea can be obtained by an empirical formula. For example, W=a/D, H=b/D,wherein a, b are predetermined empirical values, and D=√{square rootover ((x2−x1)²+(y2−y1)²)}. As shown in FIG. 5, the image in arectangular frame is the image provided by the position searching methodbased on an electronic map in accordance with the present embodiment,and the image has the width of W, the height of H, and is centered onthe dot O.

In the present embodiment, the position searching method calculates thecoordinates of the searching object in the panoramic image of a nearestscene, according to the position-related information of each scene inthe geographical area. Then, the method outputs an image generated fromthe image area that is centered on the coordinates and of apredetermined size. The method achieves the association of panoramicimages and the searching object, provides an efficient and useful mannerfor visually expressing position-related information, and helps the userto quickly find a place in the real world. Also, the method has theadvantages of low cost, less amount of data, and high accuracy of imageassociation.

One skilled in the art would know that all or part of the steps in theabove method can be achieved by instructing related hardware to finishwith one or more programs. The programs can be stored in a computerreadable medium, and examples of the computer readable medium includeROM, RAM, hard disk drives and compact disks.

Embodiment 2

FIG. 6 illustrates a block diagram of a position searching apparatusbased on an electronic map in accordance with a second embodiment of thepresent invention. For convenience of description, only parts related tothe embodiment of the present invention are shown.

The position searching apparatus based on an electronic map can beachieved in a terminal device having map searching function. In detail,the position searching apparatus may be a software module run by theterminal device, or an independent hardware integrated into the terminaldevice or run in an application system of the terminal device. Theposition searching apparatus includes a keyword receiving unit 61, aposition obtaining unit 62, a panoramic image acquiring unit 63, acoordinates calculating unit 64 and an image outputting unit 65.

The keyword receiving unit 61 is configured for receiving a keyword of asearching object.

The position obtaining unit 62 is configured for searching theelectronic map with the keyword to obtain a current geographicalposition of the searching object.

The panoramic image acquiring unit 63 is configured for acquiringpanoramic images of a plurality of scenes that are located within ageographical area around the current geographical position and of apredetermined size.

In the present embodiment, the panoramic images are corresponding to aplurality of scenes that are located within a geographical area aroundthe current geographical position and of a predetermined size, and thegeographical position of the searching object can be view from thesepanoramic images. Thus, the finally outputted image associated with thesearching object is more accurate. It is also not necessary to processall the panoramic images in a street view, and thus the workload ofprocessing position searching is reduced.

The coordinates calculating unit 64 is configured for calculatingcoordinates of the searching object in one of the panoramic imagesaccording to position-related information of each scene.

The position-related information of the scene includes the width, theheight and the heading angle of the panoramic image corresponding to thescene.

The coordinates calculating unit 64 may include:

a scene position obtaining unit 641, configured for obtaining ageographical position (x2, y2) of a nearest scene of the currentgeographical position (x1, y1) of the searching object according to thegeographical positions of all the scenes in the geographical area;

a heading angle calculating unit 642, configured for calculating aheading angle θ of the searching object in a panoramic image of thenearest scene according to the current geographic position and thegeographic position of the nearest scene; and

an image coordinates calculating unit 643, configured for calculatingthe coordinates (x0, y0) of the searching object in the panoramic imageof the nearest scene according to the heading angle θ andposition-related information of the nearest scene.

The image coordinates calculating unit 643 is configured to calculatethe coordinates (x₀, y₀) of the searching object according to thefollowing formulas:

x0=h/2;

y0=w/2+(θ−θ₀)*w/360;

wherein h, w and θ₀ represent the height, the width, and the headingangle of a panoramic image corresponding to the nearest scene,respectively, and θ represents a heading angle of the searching object.

In the present embodiment, after obtaining panoramic images of thescenes in the geographical area, the geographical position of thenearest scene can be obtained according to the geographical position ofeach of the panoramic images using the scene position obtaining unit641. The nearest scene is capable of accurately showing the geographicalposition of the searching object, and is also highly related to thesearching object. During a practical operation process, if there aremultiple nearest scenes for the searching object, generally, one of thenearest scenes whose panoramic image is facing towards the searchingobject can be selected as the nearest scene. As each scene has apreviously prepared panoramic image centered on the scene, and theposition-related information. Thus, the heading angle θ of the searchingobject in the panoramic image can be calculated according to theposition-related information of the nearest scene and the currentgeographical position of the searching object using the heading anglecalculating unit 642. Then, the coordinates (x₀, y₀) of the searchingobject in the panoramic image can be calculated according to the heighth (i.e., the number of pixels in the vertical direction), the width w(i.e., the number of pixels in the horizontal direction) of thepanoramic image, the heading angle θ0 of the nearest scene using theimage coordinates calculating unit 643. In a practical application, (x₀,y₀) should be very close to, and ideally coincide with, the position ofthe searching object in the panoramic image. Thus, compared with theknown art, the outputted position-related image is highly relative tothe searching object.

The position searching apparatus may further include: a projectionupdating unit, configured for projecting the panoramic image to generatea three-dimensional image, and updating the panoramic image to thethree-dimensional image.

In the present embodiment, the projection updating unit can achieve abetter displayed effect for the image, and thus also enhances the user'sexperience.

The image outputting unit 65 is configured for generating an image froman image area of the one of the panoramic images and outputting theimage, wherein the image area is centered on the coordinates and of apredetermined size.

The present embodiment provides a position searching apparatus based onan electronic map, which includes: a keyword receiving unit 61, aposition obtaining unit 62, a panoramic image acquiring unit 63, acoordinates calculating unit 64 and an image outputting unit 65. The keyword receiving unit 61 receives the keyword of the searching object. Theposition obtaining unit 62 searches the electronic map with the keywordto obtain a current geographical position of the searching object. Thepanoramic image acquiring unit 63 acquires panoramic images of aplurality of scenes that are located within a geographical area aroundthe current geographical position and of a predetermined size. Thus, thepanoramic image acquiring unit 63 limits the scope of the scenes shouldbe considered. Additionally, the coordinates calculating unit 64calculates coordinates of the searching object in the panoramic image ofthe nearest scene according to the height, width and heading angle ofthe panoramic images, and the heading angle of the searching object.Then, the image outputting unit 65 generates an image from an image areaof the panoramic image and outputs the image, wherein the image area iscentered on the coordinates and of a predetermined size. The positionsearching apparatus improves a correlation of the image to the searchingobject, reduces the cost of associating image to geographical positions,and also increases the utilization ratio of images.

The embodiments of the present invention obtain panoramic images inwhich the geographical position of the searching object can be viewed.Thus, the amount of the images that should be searched to find an imagefor a position is reduced. Further, a center of the image outputted canbe positioned according to the position-related information of thenearest scene. Then, the image can be obtained by cutting acorresponding panoramic image according to a user designated area, andoutputted to the user. The embodiments overcome the problems of the knowposition searching method for obtaining an image such as high cost andlow correlation to the searching object. The above embodiments canaccurately show image information for a geographical position, andtherefore enable the user to find the geographical position of thesearching object in a more quickly and accurately way. In addition, theabove embodiments can be achieved at a low cost.

The above examples may be implemented by hardware, software, firmware,or a combination thereof. For example the various methods, processes andfunctional modules described herein may be implemented by a processor(the term processor is to be interpreted broadly to include a CPU,processing unit/module, ASIC, logic module, or programmable gate array,etc.). The processes, methods and functional modules may all beperformed by a single processor or split between several processors;reference in this disclosure or the claims to a ‘processor’ should thusbe interpreted to mean ‘one or more processors’. The processes, methodsand functional modules are implemented as machine readable instructionsexecutable by one or more processors, hardware logic circuitry of theone or more processors or a combination thereof. The modules, ifmentioned in the aforesaid examples, may be combined into one module orfurther divided into a plurality of sub-modules. Further, the examplesdisclosed herein may be implemented in the form of a software product.The computer software product is stored in a non-transitory storagemedium and comprises a plurality of instructions for making a computingdevice implement the method recited in the examples of the presentdisclosure.

The above description is only illustrative embodiments of the presentinvention, and is not intended to limit the scope of the presentinvention. Any modifications, equivalent replacements and improvementsin the spirit and principle of the present invention should also beincluded in the scope of the present invention.

What is claimed is:
 1. A method for generating an image of an object onan electronic map, the method comprising: at an electronic device havingone or more processors and a display; receiving a search keyword from anend user; identifying, on the electronic map, a geographical position ofan object that matches the search keyword; selecting, among a pluralityof street-view images captured within a predefined distance from thegeographical position of the object, each street-view image havingassociated camera location and camera orientation, a desired street-viewimage whose associated camera location and camera orientation satisfy apredefined spatial relationship relative to the geographical position ofthe object; extracting a portion of the desired street-view image as animage of the object, wherein the extracted portion has a size inverselyproportional to a distance between the camera location of the desiredstreet-view image and the geographical position of the object; andoutputting the object image adjacent the geographical position of theobject on the display.
 2. The method of claim 1, further comprising:removing distortions in the extracted portion of the desired street-viewimage caused by a panoramic algorithm before outputting the objectimage.
 3. The method of claim 1, wherein selecting, among a plurality ofstreet-view images captured within a predefined distance from thegeographical position of the object, each street-view image havingassociated camera location and camera orientation, a desired street-viewimage whose associated camera location and camera orientation satisfy apredefined spatial relationship relative to the geographical position ofthe object further comprises: estimating a heading angle θ of the objectrelative to the camera location of each of the plurality of street-viewimages and then determining whether the object is within the street-viewimage by comparing the heading angle θ of the object with the cameraorientation of the street-view image; and selecting, among a subset ofthe plurality of street-view images including the object, a street-viewimage whose associated camera location is nearest to the geographicalposition of the object.
 4. The method of claim 1, wherein the extractedportion is centered on the geographical position of the object.
 5. Anapparatus, comprising: a display; one or more processors; and memorystoring one or more programs including instructions that, when executedby the one or more processors, cause the apparatus to perform operationsincluding: receiving a search keyword from an end user; identifying, onthe electronic map, a geographical position of an object that matchesthe search keyword; selecting, among a plurality of street-view imagescaptured within a predefined distance from the geographical position ofthe object, each street-view image having associated camera location andcamera orientation, a desired street-view image whose associated cameralocation and camera orientation satisfy a predefined spatialrelationship relative to the geographical position of the object;extracting a portion of the desired street-view image as an image of theobject, wherein the extracted portion has a size inversely proportionalto a distance between the camera location of the desired street-viewimage and the geographical position of the object; and outputting theobject image adjacent the geographical position of the object on thedisplay.
 6. The apparatus of claim 5, wherein the operations furthercomprise: removing distortions in the extracted portion of the desiredstreet-view image caused by a panoramic algorithm before outputting theobject image.
 7. The apparatus of claim 5, wherein the operation ofselecting, among a plurality of street-view images captured within apredefined distance from the geographical position of the object, eachstreet-view image having associated camera location and cameraorientation, a desired street-view image whose associated cameralocation and camera orientation satisfy a predefined spatialrelationship relative to the geographical position of the object furthercomprises: estimating a heading angle θ of the object relative to thecamera location of each of the plurality of street-view images and thendetermining whether the object is within the street-view image bycomparing the heading angle θ of the object with the camera orientationof the street-view image; and selecting, among a subset of the pluralityof street-view images including the object, a street-view image whoseassociated camera location is nearest to the geographical position ofthe object.
 8. The apparatus of claim 5, wherein the extracted portionis centered on the geographical position of the object.
 9. Anon-transitory computer readable storage medium storing one or moreprograms configured to be executed by a computer system, the one or moreprograms comprising instructions to perform operations including:receiving a search keyword from an end user; identifying, on theelectronic map, a geographical position of an object that matches thesearch keyword; selecting, among a plurality of street-view imagescaptured within a predefined distance from the geographical position ofthe object, each street-view image having associated camera location andcamera orientation, a desired street-view image whose associated cameralocation and camera orientation satisfy a predefined spatialrelationship relative to the geographical position of the object;extracting a portion of the desired street-view image as an image of theobject, wherein the extracted portion has a size inversely proportionalto a distance between the camera location of the desired street-viewimage and the geographical position of the object; and outputting theobject image adjacent the geographical position of the object on thedisplay.
 10. The non-transitory computer readable storage medium ofclaim 9, wherein the operations further comprise: removing distortionsin the extracted portion of the desired street-view image caused by apanoramic algorithm before outputting the object image.
 11. Thenon-transitory computer readable storage medium of claim 9, wherein theoperation of selecting, among a plurality of street-view images capturedwithin a predefined distance from the geographical position of theobject, each street-view image having associated camera location andcamera orientation, a desired street-view image whose associated cameralocation and camera orientation satisfy a predefined spatialrelationship relative to the geographical position of the object furthercomprises: estimating a heading angle θ of the object relative to thecamera location of each of the plurality of street-view images and thendetermining whether the object is within the street-view image bycomparing the heading angle θ of the object with the camera orientationof the street-view image; and selecting, among a subset of the pluralityof street-view images including the object, a street-view image whoseassociated camera location is nearest to the geographical position ofthe object.
 12. The non-transitory computer readable storage medium ofclaim 9, wherein the extracted portion is centered on the geographicalposition of the object.